NO. 1482. 



ARGEATINA FISHES— EVERMANN AND KENDALL. 



101 



The eggs of a mature female trucha were counted and measured. 

 From these data it is estimated that the trucha yields about 35,000 eggs 

 to the pound. 



In the present collection are a number of specimens 1.5 to 16.5 inches 

 long; and we have before us some specimens from Chile kindly loaned by 

 Prof, Samuel Garman, of the Museum of Comparative Zoology in Cam- 

 bridge, Massachusetts, and have examined the types of Percic/Uh//.^ 

 chilensis Girard, which are in the United States National Museum. A 

 study and comparison of this material indicate that there may be two 

 species represented. Among them are three large examples (15 to 

 10.5 inches long) which have about their heads a Scifenoid appearance, 

 as mentioned by Cuvier and Valenciennes, and b}^ Kner. There are 

 also about a dozen of smaller size (from 1.5 to 12.5 inches) which bear 

 more resemblance to a perch than to a Sci^noid. They agree with the 

 description of P. trucha Cuvier and Valenciennes and with the descrip- 

 tion and figure of P. Isevis Jenyns. 



Between these two sizes there are some notable differences, but 

 none, perhaps, which may not be accounted for by the difference in 

 size. In the large specimens the eye is somewhat smaller, the inter- 

 orbital wider, and the maxillary longer than in the others. The}' have 

 also a heavier appearance about the head, and the caudal peduncle 

 seems stouter. The evidence, however, is insuflicient to justify us in 

 regarding them as distinct. 



The following table shows the variation in proportional measure- 

 ments, etc., in the two sizes: 



Proportional measurements of PercU-ldhys trucha. 



Locality. 



Lake Traf 111.... 



Do 



Do ... 



Arroyo Coma jo 



Do 



Do 



Do 



No. 



Total 

 length 



in 

 inches. 



Head 



in 

 length 

 with- 

 out 

 caudal. 



16.5 

 16. 25 

 15 

 12.5 

 11.5 



9 



7.37 



3.33 



3.68 



3.92 



3.31 



3.62 



3 



3.10 



Depth. 



3.S8 

 3.83 

 4.45 

 3.88 

 3.52 

 3.36 

 3.29 



Eye in 

 head. 



7.13 

 7.14 

 7.39 

 6.56 

 6.14 

 6.50 

 5.26 



Snout. 



3.56 

 3.70 

 3.40 

 3.72 



3.93 

 3.57 



Pre- 

 orbital. 



5.35 

 5.26 

 5.30 

 4.82 

 4.58 

 5. 20 

 5 



Locality. 



Lake Traful . . 



Do 



Do 



Arroyo Comaj 



Do 



Do 



Do 



Scales. 



9-70-16 



10-70-17 



10-70-17 



12-70-17 



10-70-17 



10-70-17 

 10-70-17 



Dorsal fin. 



Formula. 



IX-I,11 



IX-I,11 



X-1, 11 



IX-I,10 



IX-1, 10 



IX-1, 11 

 IX-I,10 



Longest 



.spine in 



head. 



3.67 



2.57 



3.03 



2.44 



2.24 

 1.90 



Anal fin. 



Formula. 



11-1,9 



11-1,8 



11-1,9 



11-1,8 



11-1,8 



11-1,8 

 ir-1,9 



Longest 



spine in 



head. 



5.09 



6.25 



4.72 



5.65 



4.30 



4.64 

 4.16 



Number 

 of gill- 

 rakers. 



6+13 

 6+13 

 6+13 

 5+14 

 6+13 

 6+13 

 7 + 13 

 6+13 

 5+14 

 5+14 

 5+12 

 5+13 



Longest 

 gill- 

 raker 



in eye. 



i 2. 30 

 I 2. 50 



